According to a report by eMarketer.com, brands that want to reach ethnic minorities online are not doing a very good job. An April 2011 survey by Yahoo!, Mindshare and Added Value found that according to Hispanics, blacks and Asian-Americans, digital advertising does not engage them. When asked for three brands doing a good job reaching them, most said they couldn’t name even one.

One big reason was that respondents felt their ethnic groups were poorly represented in messaging. Some 78% of blacks, 74% of Hispanics and 72% of Asians surveyed agreed that diversity in ads is the best reflection of the real world. And nearly as many in each group said ads should show more of that diversity.

One way to be authentic is to reflect consumers’ core values and interests. The study found particular cultural “drivers” important to ethnic groups. For about half of blacks surveyed, music and beauty were significant. For Hispanics, a big driver was food and recipes, and for Asian-Americans, restaurants that reflect their tastes were key.

Hispanic respondents, for example, pointed out that an ad with a Hispanic family sitting down and enjoying a meal together shows that the brand knows what is important to that group.

Why have marketers been slow to understand the importance of ethnic authenticity? The researchers said that brands do understand the importance of multicultural advertising, but one of the fears is that if you make a misstep in this area, the backlash is really negative.